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991.
ABSTRACT: BACKGROUND: Goose circovirus (GCV) presents an immunosuppressive problem in production of geese. Theinfection's clinical symptoms include growth retardation or feathering disorders but theinfection process may remain non-symptomatic what makes the infected birds moresusceptible for secondary viral, bacterial and fungal infections. Diagnosis of GCV infection ismade by histopathological examination, dot blot hybridization, polymerase chain reaction(PCR) and real-time PCR. However these techniques require application of thermocyclersand qualified staff which may be cost-consuming for some diagnostic units. The aim of thisstudy was to develop loop-mediated isothermal amplification assay (LAMP) as a simplemethod of GCV detection. RESULTS: The presented study has shown LAMP as a rapid tool of detecting DNA of goose circovirus(GCV) as soon in 30 min time. The method used three sets of primers: two outer primers (F3and B3), two inner primers (FIP and BIP) and two loop primers (FL and BL) to accelerate thereaction. The optimum reaction temperature and the time were 62°C for 30 min, respectively.The results were analysed using SYBR Green dye and GelRedTM solutions. Thirty-eightisolates of GCV collected from geese flocks in Poland were examined. For comparison, realtimepolymerase chain reaction with F3 and B3 primers and SYBR Green dye wasconducted. The obtained results have shown GCV-LAMP as a sensitive, rapid and specificassay and alternative for PCR-based methods. CONCLUSIONS: The developed technique due to its simplicity may be applied by any veterinary laboratory oreven mobile diagnostics units for the routine detection of GCV. 相似文献
992.
CD44 is a protein, being a major cell surface receptor for hyaluronan (HA). Molecular modeling investigation was carried out on the murine CD44 in complex with a HA heptasaccharide in order to: (i) elucidate the nature and dynamics of interactions between the HA chain and CD44; (ii) find out if the existence of two conformational forms of CD44 discovered in the XRD (X-Ray Diffraction) study can be responsible for its switching between low and high affinity for HA. The results indicate that the contact of CD44 with HA is dominated by hydrogen bonding with small contribution of hydrophobic interactions and salt bridges. In addition, the two ('A' and 'B') conformational forms of the HA-CD44 complex reported experimentally by Banerji et al. cannot be observed during simulations when considering the distance between HA and the sidechain of the R45 residue. There exists, however, a free energy barrier associated with the change of the φ dihedral angle value at Y46. Additionally, some thermodynamic parameters (e.g. the Gibbs free energy change) accompanying the HA binding by CD44 were estimated. 相似文献
993.
Rać ME Suchy J Kurzawski G Kurlapska A Safranow K Rać M Sagasz-Tysiewicz D Krzystolik A Poncyljusz W Jakubowska K Olszewska M Krupa B Chlubek D 《Biochemical genetics》2012,50(1-2):103-111
This study investigates potential associations between CD36 gene variants and the presence of risk factors in Caucasians with coronary artery disease (CAD) manifested at a young age. The study group consisted of 90 patients; the men were ≤ 50 years old and the women were ≤ 55 years old. Amplicons of exons 4 and 5 including fragments of introns were analyzed by DHPLC. Two polymorphisms were found: IVS3-6 T/C (rs3173798) and IVS4-10 G/A (rs3211892). The C allele of the IVS3-6 T/C polymorphism was associated with higher prevalence of obesity and diabetes, higher hsCRP, lower Lp(a) serum concentrations, and younger age at myocardial infarction. The A allele of the IVS4-10 G/A polymorphism was associated with older age of myocardial infarction and higher white blood cell count. The functional role of CD36 polymorphisms in CAD development needs further research. 相似文献
994.
Selmi A Malinowski M Brutkowski W Bednarek R Cierniewski CS 《Experimental cell research》2012,318(14):1659-1666
Numerous studies have demonstrated the effects of Tβ4 on cell migration, proliferation, apoptosis and inflammation after exogenous treatment, but the mechanism by which Tβ4 functions is still unclear. Previously, we demonstrated that incubation of endothelial cells with Tβ4 induced synthesis and secretion of various proteins, including plasminogen activator inhibitor type 1 and matrix metaloproteinases. We also showed that Tβ4 interacts with Ku80, which may operate as a novel receptor for Tβ4 and mediates its intracellular activity. In this paper, we provide evidence that Tβ4 induces cellular processes without changes in the intracellular Ca(2+) concentration. External treatment of HUVECs with Tβ4 and its mutants deprived of the N-terminal tetrapeptide AcSDKP (Tβ4(AcSDKPT/4A)) or the actin-binding sequence KLKKTET (Tβ4(KLKKTET/7A)) resulted in enhanced cell migration and formation of tubular structures in Matrigel. Surprisingly, the increased cell motility caused by Tβ4 was not associated with the intracellular Ca(2+) elevation monitored with Fluo-4 NW or Fura-2 AM. Therefore, it is unlikely that externally added Tβ4 induces HUVEC migration via the surface membrane receptors known to generate Ca(2+) influx. Our data confirm the concept that externally added Tβ4 must be internalized to induce intracellular mechanisms supporting endothelial cell migration. 相似文献
995.
Kowalski W Nocon D Gamian A Kołodziej J Rakus D 《Journal of cellular physiology》2012,227(6):2613-2621
Cancer cells prefer anaerobic ATP synthesis, regardless of the availability of oxygen. It has been hypothesized that in these cells, glycolytic enzymes associate into a large complex, which results in an increased efficiency of glycolytic flux. However, there is no convincing in vivo evidence supporting this hypothesis. Here, we show that all the enzymes of triose phosphate metabolism, from aldolase to pyruvate kinase consecutively, form a macromolecular complex in vivo and that disruption of such complex significantly inhibits lactate release and ATP synthesis in the glycolytic pathway. Composition of the complex and the effectiveness of the glycolytic flux depends on lactate and glucose concentration. High concentrations of exogenous lactate reduces association of the C-terminal region phosphoglycerate mutase (PGAM) with the complex which results in its disruption and inhibition of ATP synthesis. Additionally, high lactate affects nuclear localization of PGAM and ceases cell proliferation. Our findings might provide new prospects for cancer treatment using low-molecular weight competitors to destabilize the glycolytic complex and reduce proliferative potential of cancer cells. 相似文献
996.
Bernard M. A. G. Piette Junli Liu Kasper Peeters Andrei Smertenko Timothy Hawkins Michael Deeks Roy Quinlan Wojciech J. Zakrzewski Patrick J. Hussey 《PloS one》2009,4(8)
Microtubules are self-assembling polymers whose dynamics are essential for the
normal function of cellular processes including chromosome separation and
cytokinesis. Therefore understanding what factors effect microtubule growth is
fundamental to our understanding of the control of microtubule based processes.
An important factor that determines the status of a microtubule, whether it is
growing or shrinking, is the length of the GTP tubulin microtubule cap. Here, we
derive a Monte Carlo model of the assembly and disassembly of microtubules. We
use thermodynamic laws to reduce the number of parameters of our model and, in
particular, we take into account the contribution of water to the entropy of the
system. We fit all parameters of the model from published experimental data
using the GTP tubulin dimer attachment rate and the lateral and longitudinal
binding energies of GTP and GDP tubulin dimers at both ends. Also we calculate
and incorporate the GTP hydrolysis rate. We have applied our model and can mimic
published experimental data, which formerly suggested a single layer GTP tubulin
dimer microtubule cap, to show that these data demonstrate that the GTP cap can
fluctuate and can be several microns long. 相似文献
997.
Background
Acute lymphoblastic leukemia (ALL) is a common form of cancer in children. Currently, bone marrow biopsy is used for diagnosis. Noninvasive biomarkers for the early diagnosis of pediatric ALL are urgently needed. The aim of this study was to discover potential protein biomarkers for pediatric ALL.Methods
Ninety-four pediatric ALL patients and 84 controls were randomly divided into a "training" set (45 ALL patients, 34 healthy controls) and a test set (49 ALL patients, 30 healthy controls and 30 pediatric acute myeloid leukemia (AML) patients). Serum proteomic profiles were measured using surface-enhanced laser desorption/ionization-time-of-flight mass spectroscopy (SELDI-TOF-MS). A classification model was established by Biomarker Pattern Software (BPS). Candidate protein biomarkers were purified by HPLC, identified by LC-MS/MS and validated using ProteinChip immunoassays.Results
A total of 7 protein peaks (9290 m/z, 7769 m/z, 15110 m/z, 7564 m/z, 4469 m/z, 8937 m/z, 8137 m/z) were found with differential expression levels in the sera of pediatric ALL patients and controls using SELDI-TOF-MS and then analyzed by BPS to construct a classification model in the "training" set. The sensitivity and specificity of the model were found to be 91.8%, and 90.0%, respectively, in the test set. Two candidate protein peaks (7769 and 9290 m/z) were found to be down-regulated in ALL patients, where these were identified as platelet factor 4 (PF4) and pro-platelet basic protein precursor (PBP). Two other candidate protein peaks (8137 and 8937 m/z) were found up-regulated in the sera of ALL patients, and these were identified as fragments of the complement component 3a (C3a).Conclusion
Platelet factor (PF4), connective tissue activating peptide III (CTAP-III) and two fragments of C3a may be potential protein biomarkers of pediatric ALL and used to distinguish pediatric ALL patients from healthy controls and pediatric AML patients. Further studies with additional populations or using pre-diagnostic sera are needed to confirm the importance of these findings as diagnostic markers of pediatric ALL. 相似文献998.
999.
Wojciech?BurzaEmail author Ewa?Dziadczyk Adam?Tylicki Mieczys?aw?Kura? Stefan?Malepszy 《Acta Physiologiae Plantarum》2003,25(4):385-394
A liquid meristematic root primordia culture (RPC) of Solanum lycopersicoides Dun. based on persistent rhizogenesis in a modified Murashige and Skoog (1962) medium supplemented with NAA (15 mg·l−1) or 2,4-D (1 mg·l−1) was described. The meristematic clumps (2–3 mm in diameter) originating from NAA supplemented medium were capable of regenerating
plants through the callus stage (up to 70 %). Efficient direct plant regeneration (up to 21 %) was possible from numerous
single globular-shaped root primordia (RP) structures liberated from the parental aggregates in 2,4-D supplemented proliferation
medium without NH4NO3 and with a 2.5 fold increase in KNO3. The RP converted into plantlets (artificial seedlings) on solid or liquid media without growth growth regulators through
the unipolar followed by the mace-shaped bipolar structure stages. The use of apical shoot bud, root apices or root segments
as a primary explants brought about RPC induction and plant regeneration. The plants derived from 2 years old culture were
phenotypically identical to their parental S. lycopersicoides plants and possessed the same ploidy. 相似文献
1000.
Transformation efficiencies as high as 107 transformants g–1 DNA have been previously reported for pseudomonads using electroporation protocols established for E. coli with plasmid DNAs prepared from methylation proficient E. coli hosts. We report here a protocol for electroporation of plasmid DNAs into a biocontrol strain of Pseudomonas syringae which could not be electroporated by standard E. coli methods. Transformation efficiencies of 107 or higher were obtained with DNA recovered from initial P. syringae transformation or with DNA prepared from methylation deficient E. coli. Both plasmids used in this study were stably maintained in the absence of selection for at least 50 generations. 相似文献